Portable fan



FIG. 1 is a top, front and right side perspective view of a portable fan showing our new design;

FIG. 2 is a top, back and right side perspective view thereof;

FIG. 3 is a top plan view thereof, on a reduced scale;

FIG. 4 is a front elevational view thereof, on a reduced scale;

FIG. 5 is a left side elevational view thereof, on a reduced scale;

FIG. 6 is a back elevational view thereof, on a reduced scale;

FIG. 7 is a right side elevational view thereof, on a reduced scale; and,

FIG. 8 is a bottom plan view thereof, on a reduced scale. 

The ornamental design for a portable fan, as shown. 